Reassociation

4.5.3.4 Reassociation

Association is sufficient for no-transition message delivery between IEEE 802.11 STAs. Additional
functionality is needed to support BSS-transition mobility. The additional required functionality is provided
by the reassociation service. Reassociation is one of the services in the DSS.
The reassociation service is invoked to “move” a current association from one AP to another. This keeps the
DS informed of the current mapping between AP and STA as the STA moves from BSS to BSS within an
ESS. Reassociation also enables changing association attributes of an established association while the STA
remains associated with the same AP. Reassociation is always initiated by the mobile STA.
No facilities are provided to move an RSNA during reassociation. Therefore, the old RSNA is deleted, and a
new RSNA is constructed.
4.5.3.5 Disassociation
The disassociation service is invoked when an existing association is to be terminated. Disassociation is one
of the services in the DSS.
In an ESS, this tells the DS to void existing association information. Attempts to send messages via the DS
to a disassociated STA will be unsuccessful.
The disassociation service may be invoked by either party to an association (non-AP STA or AP).
Disassociation is a notification, not a request. Disassociation cannot be refused by the receiving STA except
when management frame protection is negotiated and the message integrity check fails.
APs may disassociate STAs to enable the AP to be removed from a network for service or for other reasons.